The canine spinal column is made up of four major vertebral regions: cervical (neck), thoracic (mid back), lumbar (lower back) and sacral (pelvic). Dogs have seven cervical, thirteen thoracic, seven lumbar and three sacral vertebrae. There are also variable numbers of coccygeal or tail vertebrae. Intervertebral disks are located between the vertebral bodies starting at the second and third cervical vertebrae (C2-3) and extending to the seventh lumbar and first sacral vertebrae (L7-S1). The intervertebral disks function relatively well to withstand compressive forces, but do not function as well to combat twisting or bending forces applied to the axis (straight line down the length) of the spine.
Canine intervertebral disk disease is a disorder manifested by pain, ataxia, paresis, motor paralysis or sensorimotor paralysis, resulting from displacement of part or all of the nucleus of an intervertebral disk. This disorder is commonly seen in chondrodystrophoid breeds such as the dachshund, basset hound and beagle. The most frequently involved disks are in the thoracolumbar (mid-back) region from T11 to L2, but those in the cervical and lumber spine are also commonly affected. There are a number of other common spinal or hip disorders which canines may suffer, such as hip dysplasia. Dysplasia is considered to be a condition caused by improper growth of hip joint components, and may require surgery and extensive rehabilitation.
These types of conditions may require surgery and extensive rehabilitation. It is advantageous to provide some type of support that can be used by an owner to support at least a percentage of the animal's body weight when the animal walks or when the animal is undergoing rehabilitative therapy. For those animals that have undergone surgery, or animals that have suffered a debilitating injury, it is advantageous to provide a support harness that can be used by an owner to support the weight of the animal. Many veterinary professionals use or recommend supporting the animal by using a common household bath towel that is slung beneath the animal's abdomen, and the joined ends are grasped by the owner or handler. Obviously, this method of supporting a dog is less than optimal, and precise control and stability are clearly not capable of being obtained by this traditional method.
There are a number of patents that are directed toward harness and sling devices that utilize power lifting devices to raise four-legged livestock and other large animal off the ground for therapeutic purposes.
Miller, U.S. Pat. No. 1,015,239, discloses a horse swing that includes a canvas belt attached to a pair of longitudinally extending rods each provided with strips of canvas connected to the rods by a first set of straps extending around the rods and having buckles connected to an end of respective straps that overlap the canvas body. Chains extend from each rod to a ring, by which the swing is suspended. A breaching collar strap and a breast collar strap are attached to the canvas body and a back strap is connected to the breaching collar and breast collar.
Dunn, U.S. Pat. No. 1,277,052, discloses a sling that utilizes a double block and tackle hoist to raise a four-legged livestock animal, particularly a horse, off the ground for therapeutic purposes. The sling includes in combination; a breast band to extend in front of the forelegs, a body band, a breeching, strap connections between the breast band and body band, and between the breeching band and body band, and front and rear elevating mechanisms.
Munks, U.S. Pat. No. 4,550,686 discloses a sling that utilizes power lifting means such as a front-end loader and come-a-longs to raise a four-legged livestock animal or other large animal off the ground and hold it there for extended periods. The sling includes a pair of longitudinally extending poles; a plurality of longitudinally spaced, transversely extending straps mounted between the poles; a centrally disposed web extending between adjacent transverse straps for supporting the belly of the animal; a pair of generally longitudinally extending leg straps mounted between the transverse straps. The transverse and longitudinal leg straps and the web collectively define four leg openings and an udder/genital opening.
Alaniz et al, U.S. Pat. No. 5,823,146 discloses an animal restraining device including a restraining litter and a support frame. The frame supports the litter thereon and has features which facilitate an adjusting of the width between support members of the litter and an adjusting of the height of the frame. The litter has leg apertures therein for receiving the legs of an animal and allowing the legs to dangle below the litter. The frame has an entry side for facilitating entry of the litter with an animal therein. The litter containing the animal and legs of the animal is placed through the entry side into the interior of the frame.
Cool, U.S. Pat. No. 6,640,751, discloses an animal support apparatus that is attachable to a mobile support frame for allowing the animal to remain suspended at a predetermined height to facilitate the process of medical rehabilitation. The apparatus includes an elongate flexible sheet member for positioning about a belly and sides of an animal. The sheet member is generally oval-shaped and has a plurality of apertures for receiving the limbs of the animal. The sheet member comprises a substantially flexible cloth material and has a cushioned material attached to an inner side of the sheet member. The sheet member has a plurality of handle sections attachable to the mobile support frame for lifting the sheet member upward such that limbs of the animal are relieved of a portion of the animal's weight to facilitate the process of medical rehabilitation of one of the limbs or other related parts of the animal.
There are also a number of patents that are directed toward pet carriers, harnesses, and sling devices that are routed under the trunk of a smaller animal's body for carrying the animal or assisting a convalescing or injured animal. The following are some examples.
Hugus, U.S. Pat. No. 2,976,840 discloses a suspensory sling for animals which includes a wheeled support frame having a pair of inverted U-shapes roller-equipped end frames connected in spaced relation that extend over an animal, and a flexible sling assembly suspended from the frame for supporting the selected legs of the animal in an elevated position. The flexible sling assembly includes a flexible body part having leg openings, straps for connecting it about the animal, and suspension loops for detachably connecting the sling to the support frame adjacent respective end frames.
Doyle, U.S. Pat. No. 4,644,902 discloses a pet carrier which includes a sling of flexible sheet material having a body portion with holes for receiving the pet's legs and straps extending from the sides of the body portion which are drawn over the pet's body and secured together so that the carrier may be slung over a user's shoulder or arm or carried in the hand. A pair of restraining straps are secured to the body portion outwardly of the leg receiving holes with hook and loop fastening tapes adjustably connecting the restraining straps for snug engagement over the back of the animal to prevent it from retracting its legs from the holes thereby securely retaining the pet in the carrier.
Anderson, U.S. Pat. No. 4,831,967 discloses an animal lift frame that provides a mechanically adjustable support structure for restraint and skeletal support of an animal undergoing veterinary care. The lift frame includes a generally rectangular frame portion with front and rear beam members connected by a center beam, and right and left side rail members. The center beam carries a slidable counter balance/lifting eye member attachable to a center chain for lifting of the entire apparatus by a common hoist means. A series of adjustable length stabilizer straps extend from a point on this center chain to a fixed or adjustable lifting eye on each of the front and rear beam and right and left rail members. A harness or sling for supporting the underside of the animal is removably secured to the right and left rails.
Kitchens, U.S. Pat. No. 5,193,486 discloses a pet carrier that can be selectively converted to a pet jacket. The pet carrier includes a flexible bag-like body member having a neck brace at a forward end, a torso support portion and an integrally formed cu-shaped hind leg support portion at a rearward end. A pair of strap handles are attached to respective sides of the body member. The pet carrier is converted to a pet jacket by reversing and folding the rearward end of the body member over the forward end of the body member.
Manuel, U.S. Pat. Nos. 5,738,043 and 5,894,817 disclose small animal carriers that can also serve as a wearable garment that have left and right side panels, a bottom panel defining therebetween a neck opening, a tail opening, a pair of unrestrained lateral front leg openings, and a pair of lateral unrestrained rear leg openings symmetrically positioned on both sides of the bottom panel. A pair of opposing handles extend outwardly and upwardly from the mid sections of the left and right side panels for hand carrying the animal. Detachable D-rings are provided on the longitudinal edges of the side panels for connecting a leash or a shoulder strap.
Butchko, U.S. Pat. No. 6,216,636, discloses a device for assisting four-legged pets to walk during periods of convalescence from foot, leg, or hip surgery or injury. The device includes a sling portion connected to two opposing handle grips. The sling portion is disposed either under the chest of the animal in the case of debilitated front legs, or under the abdomen in the case of debilitated hind legs, and the handle grips are grasped by the owner help to support or lift either the front or the rear of the pet.
Solze, U.S. Pat. No. 6,631,697 discloses a support for assisting a large dog traveling on an incline which has two handles attached to opposite ends of a flexible fabric or leather support member. The first and second handles are attached to the support member at an angle consistent with the angle of incline to be traversed whereby the weight of the dog is substantially evenly dispersed along the support member where the support member contacts the dog, namely, under the front shoulders and the ribcage. When a lifting force is applied to the handles, the weight of the dog is partially supported and partially transferred to the support member resulting in the necessary support for the animal.
Muckleroy, U.S. Pat. No. 6,802,282 discloses a multi-function pet carrier having a first flexible panel overlapped perpendicularly by a second flexible panel. One of the flexible panels can be formed into pockets for carrying needed articles. The other flexible panel can be cushioned. Corners of the panels are connected with adjustable straps or strap combinations fixed to what are normally corners of the panels to form the pet carrier for wearing in a horizontal position on a bearer's body.
Moore, U.S. Pat. No. 7,325,516 discloses a mobility assistance vest for lame or elderly canines that is placed under the dog, and then right and left side sections are pulled together over the top of the animal and fastened with hook and loop fasteners. A chest section having front shoulder straps is pulled through the front legs and secured to the side sections on either side of the neck. Semi-detachable handle straps at the front legs are crossed to the opposing side and attached with a snap to D-rings on the shoulder handles for the human handler to provide counter weight or upward support as they both descend stairs side-by-side. Alternatively, the detachable handle straps at the front legs can be attached with the snap connector to the D-rings on the rear section of the vest to provide support for assisting the canine while ascending stairs, walking and standing up.
Leo, U.S. Published Patent Applications 2005/0076853 and 2005/0229869, disclose a jacket and a carrying device for domestic animals which includes a flexible element that extends around the body of the animal. A handle which can allow the animal to be carried by the person holding it, is associated with the external surface of the portion of the flexible element which is disposed next to the back of the animal.
Sherman et al, U.S. Published Patent Application 2005/0263102, discloses a wearable, multi-positional apparatus and method for transporting an animal horizontally in an adjustable, body-conforming apparatus worn about the human torso. The carrier consists of a convex shaped main body panel bound at its perimeter by flexible, semi-rigid binding material and cushioned leg openings. The body panel passes beneath and is drawn up around the animal that is secured under its hindquarters and beneath the chest area in front of the forelegs away from the esophageal area with the pet in a natural horizontal level orientation. The carrier has tote-style handles, and a multi-positional strap that permits the carrier to be draped over the shoulder, around a person's waist, across the human chest, or converted to a leash.
Beach et al, U.S. Published Patent Application 2008/0072838, discloses a pet carrier which includes a lateral support panel sized and shaped to fit beneath an abdomen of a pet. The lateral panel has a pair of foreleg openings and a pair of back leg openings sized and disposed to permit entry of the forelegs and back legs of the pet. A front support panel extends forwardly from the lateral panel adjacent the foreleg openings. A rear support panel extends rearwardly from the lateral panel adjacent the back leg openings. Side support panels are located along the sides of the lateral panel. A carrying strap is attached to the pet carrier that includes an adjustable front strap and at least one rear strap. The rear strap is attached at opposite rear corners of the carrier and loops around the front strap to provide for carrying comfort.
Rubinstein et al, U.S. Published Patent Application 2009/0314224 discloses an animal support harness and method of supporting and restraining movement of an animal. The apparatus includes a sling that can be routed around the abdomen of the animal, and a plurality of primary support straps extend from the sling and are joined at a handle. A leash strap is integrated with the handle, and extends to connect to the collar of the animal. The integral leash strap along with the primary support straps enables an owner to control not only an upward supporting force for the animal, but also provides an inherent restraint to prevent an animal from walking too quickly or lunging, which might otherwise harm the animal.
Most of the harness and sling devices that raise four-legged livestock and other large animals off the ground for therapeutic purposes are complex constructions and require power lifting devices or frames to raise and support the animal off the ground, and many incorporate straps and slings that diverge outwardly from the underside of the animal when lifted. Thus, they are not particularly suited for raising and supporting the animal by hand straps or shoulder straps.
Many of the pet carriers, harnesses, and sling devices discussed above that have shoulder straps and carrying handles for lifting and carrying smaller animals do not provide rigid horizontal support means positioned longitudinally above the full length of the animal's back and spine including the shoulder and hip areas and are incapable of evenly distributing the weight of the animal or reducing twisting or bending stresses applied to the axis of the spine.
Other pet carriers, harnesses, and sling devices that assist a convalescing or injured animal utilize straps or relatively narrow sling components that extend around or beneath only a portion of the animal's trunk and when lifted only support a designated portion of the animal's body between the front and rear legs, rather than supporting the full length of the animal's trunk and spine including the shoulder and hip areas. These types of sling devices do not evenly distribute the weight of the animal and can actually cause bending of the spinal column, thus, they are not particularly suited for preventing twisting or bending stresses applied to the axis of the spine nor suitable for lifting the animal completely clear of the ground for carrying.